I just got 2 boy rats, they are only babies and need lots of handling to tame them but they are gorgeous! I would definatly recommend them! I got 2 because keeping a lone rat is sometime considered cruel because they need companions to keep them happy when you are not there, also if you are thinking about going to a breeder or a petshop most around here only sell them in pairs because of this reason.
Have you considered going to a rescue? chances are they would be held and handled alot more than pet shops so it might be better for your daughter having a rat that is used to being held. I got told that boys are more docile than girls but I'm not sure if that is just a myth.
I found www.fancy-rats.co.uk REALLY helpful! they have a cage calculator to see how many rats are recommended in a cage and how to kit out the cages to make them exciting for them!
I got the savic freddy 2 cage for mine and they seem to have plenty of room and the door is quite big so you can fit your arms in to get to the rats which is helpful if they are shy like mine!
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